Introduction
Medicines like Wegovy (semaglutide) and Mounjaro (tirzepatide) are becoming well-known for helping people lose weight. Alongside weight loss many people also notice changes in their blood pressure whilst using these treatments.
Since high blood pressure (hypertension) is a major risk factor for heart disease and stroke, it’s important to understand how these medicines might affect it, and what you can do to stay safe and healthy along the way.
How GLP-1 Medicines Work
Wegovy and Mounjaro belong to a group of medicines called GLP-1 receptor agonists (Mounjaro also acts on another hormone called GIP). They work by:
- Helping you feel full sooner and for longer.
- Slowing digestion so you eat less.
- Supporting your body to use insulin more effectively.
The result? Weight loss, which leads to a number of powerful health benefits , one of them being the lowering of blood pressure, surprise! (1,2).
Effects on Blood Pressure
Research shows that GLP-1 medicines often lead to a drop in blood pressure, especially systolic blood pressure (the top number). On average, people see a reduction of around 5–10 mmHg. (2-4).
Wegovy (semaglutide): In clinical trials, people lost weight and their blood pressure dropped by about 5 mmHg on average—even if they didn’t have high blood pressure to begin with (2).
Mounjaro (tirzepatide): Studies like the SURMOUNT-1 trial showed a slightly larger effect, with average reductions of 7–10 mmHg in systolic blood pressure (3).
Most of this improvement comes from weight loss, but researchers also think these medicines have direct effects on blood vessels and the kidneys that help lower pressure too.(3,4)
For many patients, this is a welcome benefit. But if you already take blood pressure tablets, your readings may go too low, so careful monitoring is important.
What Patients Should Consider:
1.Before starting treatment
- Check your blood pressure: Have a baseline reading, either at home or with your GP.
- If you're currently on medication for high blood pressure or medication which may affect your blood pressure, ensure to inform your doctor of your intention to use weight loss injections, also ensure you disclose all medications to your private weight loss prescriber.
- Get blood tests: These help your healthcare team check your general health before starting.
2.During treatment
Check your blood pressure regularly: Using a simple home monitor is a simple way to keep track of your health. Record your readings to share with your Doctor.
Know the signs of low Blood Pressure (hypotension) usually defined as a reading less than 90/60 mmHg. Symptoms may include:
- Dizziness
- Light-headedness
- Fainting
- Blurred vision
- Fatigue
These symptoms may be more noticeable if you already take medication for high blood pressure, since those medications can combine with the natural blood pressure improvements which come with weight loss to lower your readings even further.
For this reason it’s important to stay in touch with your doctor: Your blood pressure medicines might need adjusting if your blood pressure improves a lot.
3.Ongoing / after weight loss
Congratulations at this stage you would have reached your ideal body weight.
Your blood pressure may have greatly improved but any changes to tablets should only be made with your doctor’s advice.
Ensure to keep monitoring: Even if blood pressure medications have been stopped, blood pressure can creep up again if old habits return. So ensure to maintain your new habits: Regular activity, a balanced diet, and good sleep.
When to seek Urgent Medical Attention
If you experience any chest pain, shortness of breath, severe dizziness, confusion, severe weakness. Please seek urgent medical attention via A&E or call 999 in an emergency.
References
- Wilding JPH, Batterham RL, Calanna S, Davies M, Van Gaal LF, Lingvay I, et al. Once-Weekly Semaglutide in Adults with Overweight or Obesity. N Engl J Med. 2021;384(11):989–1002.
- O’Neil PM, Garvey WT, Gastaldelli A, Frias JP, Lingvay I, et al. The Effect of Semaglutide on Blood Pressure in Patients without Diabetes: A Systematic Review and Meta-Analysis. J Clin Med. 2023;12(3):772.
- Chavda J, Lingvay I, Brown K, Perdomo G, Frias JP, et al. Tirzepatide and Blood Pressure Reduction: Stratified Analyses of the SURMOUNT-1 Randomised Controlled Trial. Heart. 2024. doi:10.1136/heartjnl-2024-324170.
- Wadden TA, Bailey TS, Billings LK, Davies M, Frias JP, et al. Effect of Semaglutide 2.4 mg on Use of Antihypertensive Treatment and Lipids in the STEP Clinical Trials. Obesity (Silver Spring). 2023;31(7):1685–96.
- Yale Medicine. Why Your Cardiologist May Prescribe Semaglutide (Wegovy). 2024. Available from: https://www.yalemedicine.org/news/why-your-cardiologist-may-prescribe-semaglutide-wegovy
- GoodRx. Is Mounjaro Good for Your Heart? 2023. Available from: https://www.goodrx.com/mounjaro/is-mounjaro-good-for-your-heart